1. Field of the Invention
The present invention relates generally to fluid containment bags and, more specifically, to a disposable bag for collection and containment of human bodily fluids such as urine, feces, or bile via a catheter or other connecting device.
2. Description of the Related Art
Persons who have undergone a colostomy, ileostomy or other surgical procedure involving the digestive tract may use a bag connected via a catheter or other connecting device to the stoma for collecting the effluent. Similarly, incontinent persons may use a bag connected via a catheter to their urinary tracts. Such bags typically have a flattened, rectangular shape with an opening in the top edge for receiving the fluid into the bag. The bag may also include an opening with a controllable valve in the bottom edge for periodically draining the fluid that collects in the bag.
The bag may be secured to the person's leg and concealed beneath clothing while the person moves about or may be suspended from a support while the person sleeps. The bag may include straps for securing it to a person's leg. The straps are typically made of an elastomeric material and looped through slits in a wing area or peripheral area adjacent the top and bottom peripheral edges of the bag.
Practitioners in the art have recognized several problems associated with bodily fluid collection bags. Fluid may slosh about in the bag and annoy or embarrass the wearer. In addition, fluid in the bag may backflow into the catheter, increasing the risk of infecting the wearer. Punctures as small as a pinhole can cause fluid to leak. Furthermore, odors can escape through the same path along which fluid can backflow. Even the plastic walls of certain bags are not sufficiently impermeable to odors to completely prevent their escape.
U.S. Pat. No. 4,179,367, issued to Barthell et al., describes a hydrophilic polymer in granular or powdered form that forms a stiff gel or semisolid when it mixes with a water-based fluid such as urine collected in a bag. Mixing the polymer with collected urine thus prevents it from sloshing. Perfumes or deodorizing chemicals may be mixed with the hydrophilic polymer to mask odors.
A fluid collection bag having a gellable polymer, as suggested by Barthell et al., would be as susceptible to the same backflow problem as a conventional drainable fluid collection bag. The gelled material has a curd-like consistency that is considerably more viscous than bodily fluids and thus does not slosh about. Nevertheless, the gelled material may be undesirably expelled from the bag if the bag is upset or squeezed.
Practitioners in the art have developed drainable fluid collection bags that include a one-way valve at the intake opening to reduce backflow of collected fluids into the catheter if the bag is upset or squeezed. The one-way valve typically consists of a pliable tube that extends into the bag from the intake opening. The tube has a flattened shape when empty of fluid because it has two opposing walls that meet along two seams. Fluid may enter the bag because its pressure spreads apart the opposing walls of the tube. Fluid that has thus collected in the bag closes the valve by pressing the walls of the tube together or against the inside surfaces of the walls of the bag. The tube remains closed until further fluid is introduced. This type of one-way valve is often called a "flutter valve." Examples of bodily fluid collection bags having flutter valves are disclosed in U.S. Pat. Nos. 2,883,985, issued to Evans, 3,331,421, issued to Lambert, 3,403,410, issued to Benzel, et al., and 4,581,763, issued to Olsen. The perimeters of the walls of a flutter valve may, in the closed position, define a rectangular or ribbon shape, such as those disclosed by Olsen and Evans, or a triangular or conical shape, such as those disclosed by Lambert and Benzel, et al. Flutter valves may reduce fluid backflow, but the sealing effect is rather poor and does not completely prevent backflow. Flutter valves may also allow gases and their associated odor to escape.
These problems and deficiencies are clearly felt in the art and are solved by the present invention in the manner described below.